香薷植物体内苯丙素类代谢物特征及其对铜毒胁迫的防御作用

The project is based on the frontier of international environmental ecotoxicology, through the integrated use of HPLC-ESI/TOF-MS, LC-ESI/MSn, Cryo-SEM, confocal laser, surface plasmon resonance (SPR) and etc., the separation and purification as well as structural identification of phenylpropanoid compounds in Elsholtzia plants will be done, including the analysis of MS splitting law for the phenylpropanoid compounds of the main structural types, so as to explore the variation on phenylpropanoid compounds in Elsholtzia plants in adaptation to copper toxicity. The antioxidant and prooxidant activity under copper ions will be investigated to build their structure-function relationship for the isolated phenylpropanoid compounds. Through the cell wall model from the cellulose-knockout mutant and its parent of rice genotypes, the oxidative stress of the phenylpropanoid compounds under copper ions will be studied for its role in lignin formation and cell wall thickening. Based on the physiological characteristics of high copper toxicity at earlier growth stage and later on recovery from stress induced by copper toxicity for Elshotzia splendens (Elsholtzia argyi as a control), the impact of key enzymes activity in lignification, lignin deposition and its configuration, cell wall structure as well as metabolites through the phenylpropanoid pathway in Elsholtzia plants will be investigated, at the different copper levels, with and/or without addition of exogenous phenylpropanoid class of antioxidants. Therefore, the novel phenylpropanoid compounds and their enhanced biological oxidative defense system in Elsholtzia plants will be expectedly achieved for the clarification of defense mechanism against stress induced from high copper toxicity in Elsholtzia plant.

本项目立足于国际环境生态毒理学前沿领域，综合运用HPLC-ESI/TOF-MS、LC-ESI/MSn、Cryo-SEM、激光共聚焦、表面等离子体共振（SPR）等，分离纯化和结构鉴定香薷植物体内的苯丙素类化合物，并对其中的主要结构类型进行质谱裂解规律分析，探究其在香薷植物体内适应铜毒时的变化特征。研究分离到的苯丙素类化合物在铜离子作用下的抗氧化和促氧化活性，建立其结构与功能的关系。通过以纤维素缺失突变体及其亲本的水稻基因型的细胞壁为模型，研究香薷植物苯丙素类化合物在铜离子作用下的氧化应激及其对木质素形成和细胞壁增厚的作用。并针对香薷植物初期高铜毒害和后来复原的生理特点，研究不同铜水平时，分别考察添加和不添加外源苯丙素类化合物对香薷植物木质化关键酶活性、木质素沉积及构型、细胞壁结构等的影响；期望从中发现结构新颖的苯丙素类化合物及其增强的生物氧化防御系统，阐明香薷植物对铜毒胁迫的防御机制。

本项目立足于国际环境生态毒理学前沿领域，综合运用HPLC-ESI/TOF-MS、FTIR、一维/二维NMR、高精度TEM、蛋白电泳/免疫印迹、细胞生物学技术等，分离纯化和结构鉴定香薷植物体内的活性代谢物（含苯丙素类），并对其中的主要结构类型进行质谱裂解规律分析。研究香薷植物活性代谢物（含苯丙素类）的活性，建立其多酚结构抗氧化性与活性功能的关系。通过以拟南芥野生株Ler及其突变株Paa1-1作为铜转入植物细胞的模型材料，研究拟南芥突变体及其亲本、海州香薷植物对铜胁迫的响应，分析拟南芥突变体及其亲本在铜胁迫时的细胞超微结构变化。并针对海州香薷植物初期高铜毒害和后来复原的生理特点（以拟南芥野生株Ler及其突变株Paa1-1作为对照），分析海州香薷植物中铜蛋白anti-PAA1、铜锌氧化歧化酶(CSD1&CSD2)、铜分子伴侣CCS、多酚氧化酶PPO和质体蓝素PC表达的动态变化；期望从中发现结构新颖的多酚化合物及其增强的生物氧化防御系统（香薷植物适应Cu胁迫时诱导增强的铜蛋白表达），阐明香薷植物对铜毒胁迫的防御机制。